1. Field of the Invention
The present invention relates generally to media storage libraries, and more specifically to safety measures for service personnel.
2. Background of the Invention
Current media library systems contain multiple independent robots for concurrently manipulating multiple media cartridges. The library system comprises an array of media storage cells and media cartridge players. A system of rails is used to guide robotic pods through all of the locations on the array.
The current enterprise class library has a few redundant features, such as redundant robots and the robot servo controllers. However, there are still many potential single points of failure in the robotics electrical components (i.e. main controller, interrupt controller, etc.). If a failure occurs in one of these components, it may make the unit non-operational. Currently, there is a customer demand for high availability (99.999% run time) on enterprise class tape automated libraries, which requires minimum system down time due to individual component failures.
Many types of system failures can be accommodated by automated backup systems that compensate for failed parts and maintain library function. However, even with such backup systems in place, the failed components must be serviced and/or replaced, which requires the intervention of a human operator. In addition, human intervention may be required for simple maintenance or upgrades. Ideally, such human invention should minimally impact library performance. At the same time, the safety of the human operator must also be preserved.
Normally, when a problem or system failure arises, e.g., jammed robot picker, the service person must take the library offline in order to make repairs, resulting in less library uptime and lower overall performance.
Therefore, it would be desirable to have a method for ensuring the safety of human operators who service automated libraries, while allowing the library to continue operations during the servicing.